Enhanced visible–NIR-driven photocatalytic activities over NaYF4:Yb3+, Er3+/Ag2CrO4 composite

Wide spectral responsive photocatalysts are of great importance for making full use of solar energy and broad application in highly efficient photocatalytic wastewater treatment, production of H 2 O 2 , etc. Thereinto, it is significative to open an appropriate way to extend the absorption to the NIR region, in which it accounts for ~ 49% in the solar spectrum. In this work, we synthesized successfully the new-style NaYF 4 :Yb 3+ , Er 3+ /Ag 2 CrO 4 photocatalyst via the hydrothermal and followed precipitation method, and it exhibited the more excellent photocatalytic performances than Ag 2 CrO 4 for the photocatalytic H 2 O 2 production and disposals of pollutants, such as methyl orange (MO), methylene blue (MB), rhodamine B (RhB) and tetracycline (TCs). The morphological, structural and optical behavior were investigated by XRD, SEM, N 2 adsorption/desorption, TEM, XPS, UV–Vis DRS, UC luminescence and photoelectrochemical experiments. It revealed that NaYF 4 :Yb 3+ , Er 3+ /Ag 2 CrO 4 photocatalyst presented stronger absorptive capacity in the visible–NIR region by the benign fluorescence resonance energy transfer (NaYF 4 :Yb 3+ , Er 3+ can convert near-infrared light to visible light via upconversion process), and showed more efficient charge transfer and separation than that of pure Ag 2 CrO 4 . The primary reactive species of ·O 2 − and h + by the trapping experiments played a considerable important role in the photocatalytic process. A promising potent system was suggested for the highly efficient utilization of sunlight in the enhancement of photocatalytic activities.